Electron deficient metalloporphyrins (metal complexes of 3:R.dbd.C.sub.6 F.sub.5,X,Y.dbd.F,Cl or Br) ##STR1## have been shown to be efficient catalysts for the oxidation of hydrocarbons with air in the liquid phase (Ellis and Lyons, Cat. Lett., 3, 389 1989; Lyons and Ellis, Cat. Lett. 8, 45 1991; U.S. Pat. Nos. 4,900,871; 4,970,348). Porphyrins 3 have been prepared by the condensation of unsubstituted pyrrole (1:X,Y.dbd.H) ##STR2## with the appropriate benzaldehyde (2:e.g. R.dbd.C.sub.6 F.sub.5) ##STR3## to give the meso-tetraphenylporphyrin (3:e.g. R.dbd.C.sub.6 F.sub.5,X,Y.dbd.H; Badger, Jones and Laslett, Aust. J. Chem., 17, 1028, 1964; Lindsey and Wagner, J. Org. Chem. 54, 828, 1989) followed by metal insertion [Adler, Longo, Kampos and Kim; J. Inorg. Nucl. Chem. 32 2443 (1970)] and .beta.-halogenation (U.S. Pat. Nos. 4,892,941; 4,970,348; U.S. patent application Ser. No. 07/568116; Traylor and Tsuchiya, Inorg. Chem., 26, 1338, 1987; Tsuchiya and Seno, Chem. Lett., 263 (1989)). Porphyrins of the type 3 where R.dbd.alkyl or phenyl (X,Y.dbd.H) have also been prepared by self-condensation of 2-(1-hydroxyalkyl)pyrroles 4 (R.dbd.CH.sub.3, C.sub.6, H.sub.5 etc.) ##STR4## in acid medium (Kuroda, Murase, Suzuki and Ogoshi, Tet. Lett. 30, 2411 1989).
Acid catalyzed condensation of pyrrole 1 (X, Y.dbd.H) and perfluoroalkyl aldehyde 2 (R.dbd.C.sub.n F.sub.2n+1) produce meso-tetra(perfluoroalkyl)porphyrins 3 (R.dbd.C.sub.n F.sub.2n+1 ;X,Y.dbd.H) in very low yield (U.S. Pat. Nos. 4,970,348; 5,120,882). The self condensation of 2-(2-hydroxy-1,1,1-trifluoroethyl)pyrrole according to the method reported above by Kuroda et al or under the usual acid catalysis systems do not produce the corresponding porphyrin 3 (R.dbd.CF.sub.3 ; X,Y.dbd.H). The failure of 4 where R is perfluoroalkyl to produce the porphyrin 3 can be attributed to its inability to generate the corresponding carbocation intermediate 5 by the elimination of the hydroxyl group. ##STR5##